May 1, 2007

Wherein hammers collide with rocks

The soil in the garden beside the front door has hardened to the point of resembling concrete. I spent forty minutes on the weekend hammering at it with the pick end of a geological hammer, and managed to loosen about one square inch. Seriously, I’m beginning to think the Moh hardness scale needs another entry just above diamond…

Once on a field school, we ran across this dolerite dyke. Part of the joy of a geology field school is that you get to hit a lot of rocks really hard with a hammer — all in the name of science, of course. So, there we were, twenty-odd students getting ready to hammer away at a dolerite dyke that had done nothing to nobody in two hundred million years, all so we could get some fresh (unweathered) samples to confirm that said dyke was, indeed, composed of dolerite.

For your future reference, dolerite is extremely hard. If ever you hit a rock with a hammer, and it rings like a bell, and your ears ring like bells, and your hands won’t stop shaking, and you have reverberations ringing through to the tips of your hair? Chances are that rock was dolerite. Just so you know.

Our instructors laughed and laughed. Until later that night, when we all got drunk and brought home a couple of road signs and some very unimpressed officers, but that’s a story for another time.

Geology field school was also the first time I got to see our German lecturer’s sense of humour in action. He dragged us up this hill in the middle of a rainstorm, and when we got to the top, we were standing in what looked like a graveyard.

Thick tombstones of whitish coloured rock stuck up all over the place, and with the grey clouds and the mist and the isolation, I suddenly had this vision of every horror movie villain ever crouching behind the rocks, waiting for our lecturer’s signal to pounce upon the largely unsuspecting student populace. Fortunately, being forewarned, I had my escape route planned: it consisted mostly of using my jacket as a sort of flexible sled, and sliding down the muddy hillside faster than anybody else could run.

Anyway, once we reached the graveyard, the lecturer turned to us and asked what we thought the rocks were composed of. Even the brightest guy in the class — the one who could identify a rock or mineral even when blindfolded, and with his taste buds seared by a year’s supply of Jalapeno peppers, and his fingers numbed by a century long blizzard — even he was stumped. Still, nobody wanted to admit defeat outright, so we thudded away half-heartedly with hammers for about five minutes, and then called it a day.

The lecturer grinned. “Ah,” he said, “I’m not surprised you didn’t know this rock. It is a rock that all geologists eventually encounter, but most do not like to admit it. I call it Fubar-ite.”